Lights connection water greif

[nknelsen]

I've had the same problem. In my area the salt used to keep roads ice and snow free can get into your trucks trailer connection and salt mixed with whatever electrical grease you've used can conduct enough electrical current to fool the truck into thinking there may be a trailer when there isn't one.

Brass filings from lots of plug insertions can do this as well.

I had an oldsmobile once that would continue to signal long after a turn or the signal would sometimes come on by itself. The local gm dealer quoted me many hundreds of dollars to replace the entire switch assembly. I was able to open the switch body, wipe all of the old grease (full of brass filings) and applied new grease which solved the problem completely. I drove that car for quite a few more years before scrapping it with no signal issues.


I clean both the truck connection and the trailer plug with brake clean spray and reapply electrical contact grease to the trailer connector only. I then plug the trailer into the truck several times in and out to spread the contact grease.

I would try this first before looking at the wiring.

 

[Flogger]

Clean it well. Take dielectric grease and throw it in the trash. Dielectric grease is and insulator that provides corrosion a fine home. Search Amazon for No-ox_ide A. Apply it very sparingly to each individual connector. If all goes well you will be as impressed with the product as I have been for the last 30 years.

 

[ArlyA]

If you're not seeing moisture under the door when you open it, then I'd check at the backside of the connector where the wires come in. I'd imagine it's looking for the ground circuit to have a connection. Clean the backside with contact cleaner, blow it off with air, then put some silicone sealer on to seal it up if this is where the issue is.

Looking in it, while the computer is saying "trailer is connected" there is no appreciable water amongst the dia-electric grease.

 

[dodge man]

I assume your truck has both a 7 pin and a 4 pins hookup? Have you looked at the 4 pin? I searched a F150 forum I’m a member of, a couple people had the same problem but didn’t see a clear solution. If your like me you hate having to take it to the dealer but you might have to.

 

[ArlyA]

Its still under warrante and was to the dealership last winter. While there for another reason, I asked about this trailer computer grief and they did fix it and said "you do have good dia-electric grease in it, we dried it out and that fixed it". Of course the problem did show up again later. I did peak in the 7 pin slot but do not use it. But since they dried out the 4 pin and the computer grief stopped and I did the same thing with wd40 and that stopped it as well. That proves to me the problem is a slight amount of moisture in that plug.